Questions 31-35
Among the many climatic threats that scientists _31_ global warming--stronger and more destructive hurricanes,
drought, rising sea levels, longer fire seasons–an__32__ in heat waves is the most intuitive and immediate. As greenhouse
gases __33__ by human activities continue to increase in the atmosphere, heat waves will become longer and individual days
will become hotter. Globally, the past six years have been _ 34__ . In the southwestern United States, days with triple-digit
temperatures are arriving weeks earlier than they __35__ a century ago and lingering three weeks longer.